CAMP SHORABAK, AFGHANISTAN — More than a year has passed since a Marine in Afghanistan was killed in a “green-on-blue” attack, but a pair of close calls in Helmand province this year at Afghan National Army training camps prove that insider attacks remain a high-profile threat to troops.

Marine advisers say, however, that while troops are forced to stay vigilant, improved cultural training has better-equipped them to recognize danger signs before they escalate.

Marine Corps Times previously reported that a member of the ANA had foiled a potential insider attack during a weapons class near Forward Operating Base Nolay in April, wrapping an armed fellow soldier in a bear hug after he allegedly announced that he planned to shoot an American. The paper has since learned of another incident earlier this year that was also thwarted by an Afghan soldier.

This attack came in February during a small-arms weapons course at Camp Shorabak, the ANA 215th Corps headquarters on the back side of Camp Leatherneck.

During range training, one of the Afghan soldiers taking the course turned his rifle uprange and began firing at Afghan instructors and the Marines observing them, said Maj. Ernest Adams, operations officer for the coalition team advising the Regional Corps Battle School at Shorabak.

None of the soldier’s shots connected, and the attack ended when an instructor named Abdul pushed the attacker’s weapon into the dirt, allowing Marines in guard towers overlooking the range to shoot and kill the assailant. Abdul, who was wounded by Marines as they fired on the attacker, has been nominated for a NATO service medal, Adams said. No motive for the attack was discovered in its aftermath. Asked about the attack, an Afghan instructor for the course declined to discuss the incident.

The commander of the team advising the 215th Corps, Col. Christopher Dowling, said those two events were the only insider incidents he is aware of in Helmand this year. But since he arrived in February, he said, he has redoubled efforts to ease cultural tension and to troubleshoot escalation of hostility before violence erupts. For example, during the month of Ramadan, which begins June 28, Marines will avoid cursing or using tobacco products around their Afghan counterparts, and will adjust the schedule of planned field exercises to take into account their ritual fast during daylight hours.

The Marines’ guardian angel protocol remains in effect. While policy dictates that troops cannot work with Afghan troops unaccompanied, a Marine security superviser said live-fire ranges at Camp Shorabak can have 10 or 20 guards assigned to protect coalition troops.

Dowling said he and his team are also constantly on the lookout for changes to “atmospherics” that might provoke tension. If something doesn’t feel right, he said, the Marines pull out to resume training and mentoring another day.

“I look at the Afghan newspaper every single morning before I leave my office,” Dowling said, adding that he will often ask about high-profile events, such as the deadly landslide in northern Afghanistan, or any controversy involving coalition troops.

“It only takes one knucklehead to take the train off the track,” he added.

While Dowling said he and his team don’t view the isolated insider incidents in terms of the failure or success of the overall mission, he said the Marines had to “keep their heads on a swivel” as much as ever around their Afghan partners.

“Do we trust them 100 percent? Absolutely not. The only people I trust are the Marines who wear this seal,” or other U.S. and coalition forces, Dowling said.

Dowling attributed the end of the deadly rash of insider attacks, which resulted in nine Marine deaths in four separate incidents between 2012 and 2013, to improved cultural training, which for his team has included an intensive, 14-hour-a-day class in the Dari language and scenario-based de-escalation training at Marine Corps Air Ground Combat Center Twentynine Palms, California, as well as reduced contact between Afghan and coalition troops due to the ongoing drawdown of forces in Afghanistan.

The handling of the April incident at Nolay represented a “strategic win” rather than a setback, he said.

“Not only did we not kill someone and they didn’t have the ability to kill us, but we handed it over to the Afghans and allowed them to do the interviews, investigation, and allowed their process to say, ‘either guilty or not guilty, here you go,’ ” he said.

Adams, the operations officer, said officials with the 215th Corps expressed disgust with the attack at Shorabak, while the adviser team used the incident to build trust with their Afghan counterparts.

“They really take us on board as part of their family,” he said. “So that incident really insulted them and their culture, and they felt really offended by it. But we didn’t take offense to them and we stayed close.”